Bending machine with pivoted bender carrying a work supporting arm



Sept. 14; 1948. w. E. P ETTERSEN 2,449,409

BENDING MACHINE WITH PIVOTED BENDER CARRYING A WORK SUPPORTING ARM Filed NOV. 19, 1945 s Sheets-Sheet 1' Mae: 5 5776116 IN V EN TOR.

BY WM p 14, 1943- w. E. PETTERSEN 2,449,409

' BENDING" MACHINE WITH PIV'OTED *BENDER CARRYING A WORK SUPPORTING ARM Filed Nov. 19, 1945 s Sheets-Shea 2 Q INVENTOR.

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Sept. 14, 1948. w. E. PETTERSEN 9,

BENDING MACHINE WITH PIVOTED BENDER CARRYING A WORK SUPPORTING ARM Filed Nov. 19, 1945 3 Sheets-Sheet 3 MLBER E, PETTE R5EN INVEN TOR Evie/M16151 ATTORNE Y Patented Sept. 14, 1948 BENDING MACHINE WITH PIVOTED BENDEB CARRYING A WORK SUPPORTING ARM Wilber E. Pet'tcrsen, Akron, Ohio, assignor, by

mesne assignments, to Coleman-Pettersen Corporation Cleveland, Ohio, a corporation of Ohio Application November 19, 1945, Serial No. 629,437

5 Claims. (c1. 153-40) This invention relates to wire-bending machines such as are employed for bending lengths of wire to predetermined configurations comprising one or more bends and a plurality'of straight reaches.

Its chief objects are r to provide a machine adapted for rapid production of bent wire products of either a single or successively different configurations; to provide a machine adapted for quick and accurate re-setting for products of different configurations and to do that with few and inexpensive parts; to provide for automatic manipulation by the machine of parts of the wire lengths anterior to the bending operation; to prvide for power operation, as distinguished from manual operation, of the machine; and. to provide for ready control of the amount of fo-rceapplied in the bending operation in accordance with the bend-resistance of the wire being operated upon, so as to bend the wire only to such form that upon release of the bending force the wire will recoil accuratelyto the configuration desired in the product.

Of the accompanying drawings: i Fig. 1 is a plan view of a machine embodyin myinventionin its preferred form, parts being broken away for clearness of illustration.

Fig. 2 is an elevation of air-supplying devices constituting a part of the machine shown in Fig. 1

Fig. 3 is an end elevation of the machine with parts broken awa and with parts sectioned on line 3-3 of Fig. 1. a

Fig. 4 is a fragmentary section on lined-4 of Fig. V

Fig. 5 is a section on line 5-5 of Fig. 1..

Fig. 6 is a section on line 55 of Fig. 1.

Fig. '7 is a side elevation of the machine, with parts broken away and with a part in section on line 1-'| of Fig. 1. a

Referring to the drawings, the machine comprises a metal slab or table l0 suitably supported by a frame II but with a clearance space of considerable vertical dimension between the table I0 and the frame I I throughout a large part of the lower right-hand part of thetable as viewed in Fig. 1. This clearance, for the horizontal swinging movement of a work-supporting arm, can be visualized in looking at Figs. 3 and 7. (Note the table-supporting members Illa and Nb in those figures.) I

Fixedly seated in a transverse guide-groove l2 formed in the upper face of the table and held by a cap-screw [3 extending through the floor ofthe groove (Fig. 4) is a bending-jaw member M 2 i r which has a rectangular base portion fitting in the groove l2 and a triangular upper portion projecting upward from the upper face of the table and providing an acute angled vertical edge Ma for the bending of the wire about it.

A companion bending jaw member l5 mounted for sliding adjustment in the groove I2 is formed with a downwardly sloping rear face which is notched to provide a seat-for the end 'of an adjusting bolt 16 which is threaded through a bracket l1 secured to an edge face of the table. For holdingthe bending-jaw member IS in its positions of adjustment a clamping bolt l8 extends vertically through it and through a slot l9 formed in the floor ofthe groove l2. l

The bending-arm, 20, adapted to coact. with the jaws l 4, l 5, is secured on the upper end of a shaft 2| journaled in a bushing 22 (Fig. 3) which is mounted in the table and secured on the lower end of the shaft 2| is a gear 23 which is meshed with a rack 24. i The rack is. guided and held in mesh. with the gear by a bracket 2-5 extending downward from the table and the rack is coupled to the piston rod.26 of a double-acting air cylinder 21 mounted under and supported from the.

table.

Secured to the under side of the gear23 by means of two spacing brackets. such as the bracket 28 (Fig. 3), welded to respective spokes of the gear. is a sleeve 29 in which is secured, by a set-screw 30, the inner end of a horizontal rod 3| the outer end of which extends beyond the ad jacent end of the table and has secured thereon a vertical wire-supporting bracket 32 formed with an upwardly open wire-receiving notch 33 in its ting a different bracket 32 for every diameter of said oiT-setting is such that throughout the bending operation, whether the wire is bent to more or less than a right-angle, or to a right-angle, the bending edge Ma, the bending lip 20a of the jaw, and the notch 33 of the bracket 32, will be approximately in alignment at all times, as illustrated by thedotted line position of the rod in Fig. 1.

The usual end-stops 34, 34 for the wires are mounted in a through slot 35 formed in the table, each stop being formed, as clearly shown in Fig. 5, with a slot-fitting tongue non-symmetrically positioned on its lower end, and is held in selec-.

tive positions of adjustment by a screw or bolt 36 extending vertically through it at the position orv its tongue and screwed into'a tongued'or flanged nut 31 fitting into the slot from below, The stops are thus adapted to be set in a position, as in the case of the right-hand one in Fig. 1, such that a straight reach of wire from the jaws l4, is can extend past it. For acting as stops against the sidefaces of portions of thewires posterior to the bending. jawsl l, I5, one or more eccentrically mounted cylindrical blocks such as the block 38 is or are mounted upon the. upper face of the table, the block being held in selectively different rotative positions about its eccentric axis by a screw 39 extending vertically through it and screwed into one of a spaced series of tapped holes, 40, 49 extending part way through. the table, as shown clearly in Fig. 6. As each block is adapted forinfinitely small increments of adjustment, and can be set in one or another of the holes of the series, a single, straight row of the holes 40 is suflicient for the usual range of operations.

Similarly the table is formed with a field of spaced holes 40a, 48a near the bending jaw M for the mounting in that region, at locations determined by the holes and in selective rotative positions, a cylindrical, eccentrically mounted block 38a corresponding to the block 38 as just described, the block 330. being adapted to act as a stop against the portion of the Wire anterior to the jaws I4, l and by its resistance, through the 3 stifiness of the wire, to stop the bending-arm 28 at a position such that the wire will have permanent set with the desired angle of permanent bend. The block 38a is of such size and of such eccentricity, in relation to the positioning of the holes 40a, that infinitely small variations of adjustment can be had throughout the required range of operations.

For actuating the pressure fluid cylinder 21, a treadle 4i, operable from either side of the table, is hinged on a middle axis 42 (see Figs. 3 and 7) tothe end structures of the frame and each side of it is connected by a pull-cable 43 with the lever 44 oft-he cylinders four way control valve 45 having exhaust vents 45a, 45b for the two ends of the cylinder.

For supplying compressed air to the cylinder an air supply pipe 46 (Fig. 2-) from a suitable source leads, through a filter 41, a regulator valve 48, an oiler 49 and a pipe 58, to the four-waycontrolvalve 4510f the cylinder.

The regulating. valve 48 is adapted to maintain a constant air pressure in the pipe 50 according to the. setting of the valve, and the valve is set for such pressure in relation to the bend-resistance of the wire that the bending arm 20 will: have only such force as to bend the Wire to a position determined by the position of the block 33a without imparting permanent set to the wire between its bend at the bending ed ev 1.4a and the block.

The proper pressure in the pipe 50 of course depends upon both the diameter of the wire operated upon and the number of wires in the stack and also in some cases and to some extent upon the length of the reach of wire between the bending edge Ma and the block 38a.

The operation of the machine is asfollows:

The rack 24 being in its right hand position as viewed in Fig. 1 and the work-contacting members consequently being in the positions in which they are there shown; the wires I60, H10, that are to be bent, of Which three are shown in Fig. 7, are mounted in stacked relation as is shown in Fig. 7 and in contact with the several work-engaging members as shown, with regard to the top one of the wires,.in Fig. 1. V The left-hand one of the stops 34 (Fig. 1) is in its end-stop position and is abutted by the adjacent ends of the wires; the right-hand one of the stops 34 is in such position that it permits'the Wires to extend past it and does not serve as an end-stop; and the eccentric block 36, the acuteangled bending-jaw member l4 and a vertical wall of the notch 33. in the bracket 32 serve as three-point lateral supports for the stack of wires, which are in a slightly bent condition by reason of the offset of the rod 31 and the notch of its bracket 32, as above described, and, as above stated, the bending strain upon the stack of wires helps to keep a plurality of wires accurately stacked in contact with those threemembars for concurrent action upon them by the bending arm 20.

The Work and the bending instrumentalities being as just stated, the cylinder 2'! is charged to move the rack 24 to the left as. viewedin Fig. l, which causes rotation, clockwise asthere viewed, of the gear 23, the bending arm 20 and the wire'e supporting rod 3|, which bends the wires Illll to the shape that is indicated by dotted lines in Fig. 1.

The work-supporting bracket 32 clears the corner of the table H! by reason of the fact that it, as Well as the cornerof the table, is at a long radius from the shaft 2 l, as contemplated by the breakaway lines near the right-hand end of Fig. 1. I

As above stated, the pressure of air supplied to th cylinder is so controlled by means of the regulating valve 48 that the eccentric stop38a, in being contacted by the swinging portions of the wires, limits the movement of the bending arm 20, and this provision for so limiting it, with fine adjustability of the eccentric stop 380., provides conveniently for great accuracy in bending: successive stacks of wires to the same shape, as contemplated in one part of the above statement of objects.

Upon completion of the operation as just described the bent wires are removed from the machine, for further manipulation or for use in the form to which they have been bent, and the cylinder 21 is then reversed to return the moving parts of the machine to the wire-receiving positions in which they are shown in Fig. 1.

I claim:

1. A bending machine comprising stationary members for engaging opposite faces of a length of wire to maintain the position of a portion of the Wire, a movable bending member for coacting with said stationary members for bending the wire, a pressure-fluid cylinder for actuating said bending member, an adjustable stop adaptedto be. engaged by the moving portion of the wire, only and'at all times at. a greater distancefrorn the bending position than that of the saict bending members engagement with the wire, to limit the movement of said portion, wholly b such engagement, and thus to stop the said bending member wholly through bending-resistance of the wire, and means for so controlling the maxi mum pressure of fluid supplied to said cylinder, in appropriate relation to the bend-resistance of the wire, that said stop is effective to limit the movement of the bending member without distortion beyond its elastic limit of wire between said bending member and said stop.

2. A bending machine comprising stationary members for engaging opposite faces of a length of wire to maintain the position of a portion of the Wire, a movable bending member for coacting with said stationary members for bending the wire, a pressure-fluid cylinder for actuating said bending member, an adjustable stop adapted to be engaged by the moving portion of the wire,

only at a distance from the bending position, to

limit the movement of said portion Wholly by such engagement, a Work-supporting member engaging the wire still farther from the bending position and moving in correlation with the bend ing member for supporting and controlling the movement of the moving portion of the wire, and means for so controlling the maximum pressure of fluid supplied to said cylinder, in relation to the bend-resistance of the wire, that said stop is effective to limit the bending movement of the bending member without distortion beyond its elastic limit of wire between the bending member and said work-supporting member.

3. A bending machine comprising stationary members for engaging opposite faces of a length of wire to maintain the position of a portion of the Wire, a ,pivotally mounted bending member for coacting with said stationary members for bending the wire, means for moving said bending member about its pivotal axis for bending the wire and work supporting means pivotally mounted on the same axis with the bending member for movement therewith and engaging the moving portion of the Wire at a .position more remote from the bending position than is that of said bending member, the said work-supporting member having a face for forcing the wire in the direction of the bending movement and said face being, at starting position, so off-set as to hold the wire under a light bending strain, Within its elastic limit, before the functioning of said bending member.

4. A bending machine comprising stationary members for engaging opposite faces of a length of wire to maintain the position of a portion of the Wire, a movable bending member for coacting with said stationary members for bending the wire, means for applying a determinately limited actuating force to said bending member, and stop means engaging the wire only and always at a position farther from the bending position than that of the bending members wire-engaging part and acting wholly by applying only bending force to the moving portion of the wire and. being the only means for stopping the movement of the bending member.

5. A bending machine comprising stationary members for engaging opposite faces of a length of wire to maintain the position of a portion of the wire, a pivotally mounted bending member for coacting with said stationary members for bending the Wire, a shaft constituting a mounting for said bending member, a drive member coaxially secured to said shaft, and a work-sup porting arm rigid with said bending member, shaft and drive member to move therewith and extending to a position farther from the shaft than that of the bending members wire engaging part, for engaging the wire at that farther position.

WILB-ER E. PETTERSEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 468,584 Symonds Feb, 9, 1892 493,390 Stirling Mar. 14, 1893 1,024,740 Murphy Apr. 30, 1912 1,125,241 Wilson Jan. 19, 1915 1,177,262 O'Donnell Mar. 28, 1916 1,465,733 Holmgreen Aug. 21, 1923 1,512,002 Kardong Oct. 14, 1924 1,683,366 Macomber Sept. 4, 1928 1,695,836 Witmer Dec. 18, 1928 1,820,426 Beghetti Aug. 25, 1931 1,968,010 Bailey July 31, 1934 2,128,620 Lyons Aug. 30, 1938 2,305,850 Drysdale Dec. 122, 1942 2,341,178 Duer Feb. 8,.1944 2,357,027 Seifried Aug. 29, 1944 FOREIGN PATENTS Number Country Date 72,895 Germany Jan, 10, 1894 

